<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="js/vue.js"></script>
</head>
<body>
    <div id="app">
        {{msg}}
    </div>
    <script>
        var vm=new Vue({
        el:'#app',
        data:{
            msg:"ok"
        },
        beforeMount() {
            console.log('挂载之前');
            console.log(this.$el.innerHTML);//通过this.$el获取el的DOM元素
        },
        mounted() {
            console.log('挂载之后');
            console.log(this.$el.innerHTML);
        },
        })
    </script>
</body>
</html>